The use of buoys for communication platforms for off shore and near shore communication is well known in the art but maintaining constant communication between such platforms, or between such platforms and the shore, such as would be required to have an Ethernet Local Area Network (LAN) operating, has been difficult and expensive due to the constant up and down movement (heave), side to side movement (roll), and rotating movement (yaw) of buoy communication platforms when the forces of waves and currents are exerted against them. This is particularly true near shore where these forces can be more exaggerated and changing.
Present off shore and near shore communication systems normally use discus buoys for the communication platform. Because of the flat nature of these buoys they ride on the top of and follow the waves. This creates the heave, roll, and yaw problems mentioned above and thus they generally require a minimum three axis positioner for signal aiming if any communications link is required to remain unbroken by misalignment of the signal. This is costly because it requires complicated positioning calculations and constant adjusting of the signal aiming device. They also have a strong potential for capsizing. Because of the problems with discus buoys, spar buoys, which are essentially decoupled from waves, are being looked at more often as a platform for off shore and near shore communication systems. But, they still have heave (although it is not as large), very little role, and yaw is still a problem. Numerous attempts to solve these problems have been disclosed in the prior art as shown by the following patents:
U.S. Pat. No. 4,004,308 discloses a stabilizing structure for a buoyant elongated cylindrical housing assembly tethered to an anchor on the bottom of a body of water. It includes a pair of positively buoyant arms hinged to the top of the housing at an angle to each other with leaf spring members and cables attached to the ends of the leaf spring members to limit the upward travel. The outwardly extending arms have an airfoil-like cross section and assume a trailing position relative to any current in the water with the current bisecting an angle between the arms. This arrangement causes the arms to exert a lifting force tending too both rotate the housing toward the vertical around its point of attachment with the tethering line attached to its lower end in opposition to the tilting force exerted by the current and also to positively lift the housing to a higher position more nearly over the anchor. A pair of tip fins may be used to counter forces tending to move the assembly in yaw. A pair of short strips may be attached along the sides of the housing to minimize vortex shedding effects.
U.S. Pat. No. 5,108,326 relates generally to the stabilization of drifter buoys and the like and more particularly to surface or near surface Langrangian Drifter Buoys launched from aircraft or surface vehicles. It uses a underwater suspension system adapted for stabilizing and maintaining the buoy at a predetermined depth in an upright position. The suspension assembly for use in combination with a buoy, having a generally elongated cylindrical hull, is comprised of two main components including 1) a collapsible longitudinal stabilizer for providing horizontal drag and 2) a vertical stabilizer suspended below and transverse the axis of the buoy. These two components act together to maintain the buoy in an upright position and to maintain it within the layer of water in which it is placed.
U.S. Pat. No. 3,755,836 discloses an invention which works with a communications buoy of the type launched from a submerged vessel. It has an automatically deployable surface stabilization arrangement for preventing inundation of the buoy even under severe conditions. This arrangement is a collar of continuous and flexible material such as mylar film arranged around the buoy proximate to the water line, and attached to the buoy via the top portion in substantially leak-proof manner with the bottom portion open in a conical or umbrella-like fashion. The collar is rapidly deployed by a series of spring-loaded or bowed arms fabricated of a resilient material and spaced from one another around the buoy. Release of the force constraining the arms against the buoy, such as occurs upon launch of the buoy from the submerged vessel, permits the collar to automatically deploy, thus forming around the buoy at the water line a pocket to trap air. Spring-loaded fins may also be provided on a submerged portion of the buoy remote from the collar to provide broad surfaces for further damping of the forces acting on the buoy.
U.S. Pat. No. 5,387,144 also discloses a spar buoy in which a buoyancy body is provided halfway on a marker mast, the lower end of the marker mast being pulled in the water so that the water line comes to halfway on the marker mast above the buoyancy body. The spar buoy is made up of at least two arms which protrude in opposite directions to each other from the marker mast below the buoyancy body, with blades attached to the end of each arm so they have a positive angle of attack toward the center of the buoy.
The limitations of the prior art are clear. They generally attempt to use deployable or fixed mechanisms; either arms or parachute like films, around the buoy. These mechanisms are complicated and would tend to be expensive to manufacture and maintain. What is needed by the scientific and research communities is a simple stabilized buoy communication platform which is easy to deploy and maintain, and, is capable of maintaining a constant communications link with a simple one axis positioner. This invention supplies such a platform.